/ 6 October 2023

Gauteng: Same water, seven million more people

Water Qwa Qwa 4658 Dv
Gauteng water users need to use water ‘more carefully and efficiently’, says water expert. (Delwyn Verasamy/M&G)

A “perfect storm” of events has given rise to “short-term, quite local” water problems in Gauteng, according to Mike Muller, a visiting adjunct professor at the Wits School of Governance.

But most people “miss the bigger problem”, he said. “The population of Gauteng has grown from around nine million the last time the region’s supply was increased in 2004, by the completion of Mohale Dam in Lesotho. Today, the population is over 16 million but the amount of water available remains the same.” 

The available water will only increase by 2028 if the Polihali Dam, Lesotho Highlands Water Phase 2, is completed on schedule. By that time the population of Gauteng will be almost 18 million, said Muller, who was formerly the director general at the department of water affairs and forestry.

It’s “almost traditional” for water outages to occur in October “where very hot weather ahead of the first rains causes a spike in consumption that puts a strain on the capacity of local reservoirs”. 

“Then there is the contribution of load-shedding, which has reduced pumping, again in some of the smaller distribution points but may have caused some tripping of larger Rand Water pumps, reducing the delivery of water to the municipal reservoirs,” Muller said.. 

“And some of those reservoirs may not provide enough reserves to support daytime peak demands in their little supply areas (which is not a systemic problem but very distressing for the people affected).”

Perhaps the more important long term question is how secure is the supply from the Integrated Vaal River System, said Muller.

“As he [Minister of Water and Sanitation Senzo Mchunu] explained, Rand Water was sticking to the limit of its abstraction licence which, over these last weeks, was not enough to meet the demand, a situation that has been aggravated by load-shedding related pumping interruptions.  

“When, last year, the dams were so full, thanks to La Niña, the ‘little girl’ of global weather who had been smiling on us for the last three years, Minister Mchunu was advised that he could allow Rand to exceed the abstraction limit, temporarily, for a few weeks to relieve the pressure.”

Mchunu, Muller said, could perhaps do the same again for a few weeks if the weather heats up again. “But if we take more now, we will have to use less later, the limit will have to be maintained. Otherwise, we risk reducing the storage of the system. 

“Then, if there is a major drought, Gauteng and surrounding regions will face more severe restrictions.” And there is a real possibility of an El Niño multi-year drought “for which we must be prepared”.

This is another wake-up call. “We have reached the limit of the safe yield that can come from the existing dams and, until the new supply comes in in 2028, we will need to use water more carefully and efficiently.” 

That will require coordinated action by everyone from the minister downwards, including Rand Water, provincial government, municipalities and the users themselves, he said.

As part of this, there will have to be better communication with users. “Ideally, in every community, householders should know which local reservoir their water comes from, how much is being used every month and what target they should be trying to reach as a household and as a community that shares a local water network,” he said. 

There will have to be better performance by municipalities on leak management as well as metering and billing to reduce non-revenue water that is lost through leaks or taken by unauthorised users and not monitored, Muller said.

All users, householders as well as businesses and public institutions, like schools, should be helped to track and reduce their water use. “They should be told, monthly, how their usage compares with last month and how it compares with their neighbours.  And the state of the reserves in the Vaal river system should be regularly reported and people told whether the region’s water use is on track or still too high.”

That approach, Muller said, could avoid Gauteng and the other areas served by Rand Water “from suffering a Cape Town style ‘Day Zero’ event when we return to ‘normal’ drier seasons.”